When inside a plt entry jump slot you cannot always get reliably backtrace on x86_64 until you are outside the plt entry itself (and into the shared library function). Although you cannot easily step into a plt entry currently, it can happen that a backtrace is captured just at the moment one thread is inside a plt entry. In that case a single entry backtrace is produced instead of a full backtrace. Upstream has patches for stepping into (all architectures) and producing full backtraces from plt entries (x86_64): http://sourceware.org/ml/frysk/2008-q1/msg00173.html http://sourceware.org/ml/frysk/2008-q1/msg00174.html Also tracked upstream as: http://sourceware.org/bugzilla/show_bug.cgi?id=5962